Research On Design And Realization Of Two-Layer Wireless Sensor Networks For Large Scale Localization

Wireless Sensor Networks(WSN) is a popular research direction in the computernetwork area, and is considered to be one of the most important technology in 21thcentury. It will have great effects to human lifestyle in future. Also, to determine thelocation of the incident or the location of the node which obtains information, is oneof the most basic functions to sensor nodes, and plays a key role in the effectivenessof the applications of WSN. But the original WSN, as the sensor nodes'energy, com-munications, computing and storage capacity are limited, the stability of its wirelesscommunications is not enough and the communication distance is much short. Thoughwe can improve it by using good communication protocol or physical layer protocolin small scale applications of WSN, However, in large scale applications, it will resultin the entire network data lost, long time delays, and even crash the whole network.In this paper, we introduced the concept of Wireless Mesh Network(WMN) in largescale localization applications of WSN, and design the communication network andthe sensor network of localization respectively, realize a two-layer WSN.The communication network is designed based on 802.11b, and realized the trans-mit of data on wireless network adapter as the thinking of WMN. 802.11b has largedata bandwidth, efficient network, consummately communication protocol and secu-rity mechanisms, wide communication scope, and can meed the demand of commu-nication effectively. The nodes on communications network include the sink node oflocalization sensor network, normal computers and pocketable equipment which sup-port 802.11b. These nodes will assume the role of data communications and transmitthe data. Also they will be management or query terminals, manage the action of lo-calization sensor network or get the position information at any time. In order to dothese, we have transplanted the driver of wireless adapter on the sink node, and realizeddriver of some extended devices on it.The localization sensor network will be focused on sensor work and localization,use RSSI to build a map of signal strength and get the localization. Additional, westudy the QoS of WSN to control the node number in an area, give an improved nodenumber control strategy based on Gur Game. The simulation shows that the numberof power-up nodes in the focused area dynamically regulates with the total number ofnodes and meets the requirement of QoS.